Eat Your Fish Sandwich, Live Longer

Eating fish could reduce your risk of dying by more than 25%, according to a new study from the Harvard School of Public Health and the University of Washington.

Scientists found that older adults with the highest levels of fatty acids found in fish lived 2.2 years longer on average than those with lower levels.

"Although eating fish has long been considered part of a healthy diet, few studies have assessed blood omega-3 levels and total deaths in older adults," lead author Dariush Mozaffarian, associate professor in the Department of Epidemiology at Harvard, said in a press release. "Our findings support the importance of adequate blood omega-3 levels for cardiovascular health, and suggest that later in life these benefits could actually extend the years of remaining life."

Researchers have previously linked the consumption of fish -- which is rich in protein and heart-healthy fatty acids -- with a reduced risk of dying from heart disease. But this is the first time scientists have linked levels of fish consumption with death rates.

The study analyzed 16 years of data on 2,700 healthy U.S. adults ages 65 or older who participated in the Cardiovascular Health Study (CHS). Scientists tested the total proportion of blood omega-3 fatty acids -- including three specific ones -- in participants' blood samples at baseline. After adjusting for dietary, lifestyle and other factors, they found that the fatty acids were linked with a significantly lower risk of mortality.

One type in particular -- docosahexaenoic acid (DHA) -- was most strongly related to a 40% lower risk of coronary heart disease death. Of the other blood fatty acids measured -- eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA) -- DPA was most strongly associated with lower risk of stroke death, and EPA most strongly linked with lower risk of nonfatal heart attack, according to the press release. None of the participants took fish oil supplements.

Those who ate more fatty fish decreased their mortality risk from heart disease by about 35%. Overall, participants with the highest levels of all three types of fatty acids had a 27% lower risk of total mortality due to all causes.

And it doesn't take a ton of fish to gain the protective benefits.

"The findings suggest that the biggest bang-for-your-buck is for going from no intake to modest intake, or about two servings of fatty fish per week," Mozaffarian said. Those fish include mackerel, trout, tuna, salmon, herring, sardines and anchovies.